1. Field of the Invention
This invention relates to an improvement of a filter apparatus for cameras used in filter photography.
2. Description of the Prior Art
A camera containing a filter used in filter photography has been previously proposed (for example, U.S. patent application Ser. No. 765,330 filed by the applicants of this invention, now U.S. Pat. No. 4,681,418.
However, problems remain to be solved in such a conventional camera filter apparatus. For example, mistakes may be made resulting in a filter being left in place in the optical path when an ordinary photograph is to be taken, and the surface of the filter may be damaged, resulting in deterioration in the optical performance.